Long-range phase synchronization of high-gamma activity in human cortex

Arnulfo, G.; Wang, S.; Williams, N.; Hirvonen, J.; Fato, M.; Nobili, L.; Cardinale, F.; Rubino, A.; Zhigalov, A.; Palva, S.; Palva, J.

doi:10.1101/442251

bioRxiv · 10.1101/442251

Long-range phase synchronization of high-gamma activity in human cortex

Arnulfo, G.·Wang, S.·Williams, N.·Hirvonen, J.·Fato, M.·Nobili, L.·Cardinale, F.·Rubino, A.·Zhigalov, A.·Palva, S.·Palva, J.

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Abstract

Inter-areal synchronization of neuronal oscillations below 100 Hz is ubiquitous in cortical circuitry and thought to regulate neuronal communication. In contrast, faster activities are generally considered to be exclusively local-circuit phenomena. We show with human intracerebral recordings that 100-300 Hz high-gamma activity (HGA) may be synchronized between widely distributed regions. HGA synchronization was not attributable to artefacts or to epileptic pathophysiology. Instead, HGA synchronization exhibited a reliable cortical connectivity and community structures, and a laminar profile opposite to that of lower frequencies. Importantly, HGA synchronization among functional brain systems during non-REM sleep was distinct from that in resting state. Moreover, HGA synchronization was transiently enhanced for correctly inhibited responses in a Go/NoGo task. These findings show that HGA synchronization constitutes a new, functionally significant form of neuronal spike-timing relationships in brain activity. We suggest that HGA synchronization reflects the temporal microstructure of spiking-based neuronal communication per se in cortical circuits.

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Arnulfo, G., Wang, S., Williams, N., Hirvonen, J., Fato, M., Nobili, L., Cardinale, F., Rubino, A., Zhigalov, A., Palva, S., Palva, J.. 2018-10-15. Long-range phase synchronization of high-gamma activity in human cortex. https://doi.org/10.1101/442251

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